Refrigeration apparatus



Oct. 31, 1961 A. G. BuTscH 3,006,156 REFRIGERATION APPARATUS Filed oct. 1, 1959 J 39 20 INVENTOR ALFRED G. BUTSCH BY W4 H l S ATTORNEY 3,606,156 REFRIGERATIN APPARATUS Alfred G. Butsch, Louisville, Ky., assigner to General Electric Company, a corporation of New York Filed Oct. 1, 1959, Ser. No. 843,732 2 Claims. (Clem-227) The present invention relates to refrigeration apparatus and is more particularly concerned with an evaporator unit for a refrigeration system including improved means for clamping a control bulb to that unit.

In the copending application Serial No. 832,221 led August 7, 1959, in the names of Alfred G. J anos, Douglas A. Solley, Jr. and Kenneth A. Robbie and assigned to the same assignee as the present invention, there is described and claimed a defrostable evaporator unit comprising an evaporator coil enclosed Within a housing through which air is forced by means of a fan. The evaporator coil comprises parallel refrigerating and defrost tubes which are integrally connected throughout their lengths, the refrigerating tube being connected into the system to conduct low pressure refrigerant for cooling purposes, and the defrost tube being connected in the system for the purpose of periodically conducting hot compressed refrigerant for the defrosting of the evaporator coil. As part of the control circuit for controlling the Yoperation of the refrigerating mechanism, there is provided a sensing or control bulb in contact with a portion of the evaporator coil, the sensing bulb being part of a thermally operated switch arrangement for sensing the termination of the defrost cycle and returning the system to normal refrigerating operation.

The present invention has as its principal object the provision of an improved arrangement for clamping a control bulb to the evaporator coil by means of a clamp which permits the control bulb to be inserted into the housing and clamped to the evaporator coil after assembly ofthe coil and the remaining refrigerating system into the refrigerator cabinet.

Further objects and advantages of the present invention will become apparent from the following description thereof, reference being made to the accompanying drawings, and the features of novelty which characterize the invention will be pointed out with particularity in the claims annexed to and forming part of this specification.

In the drawings:

FIG. l is a side elevational View, partially in section, of a refrigerator cabinet incorporating an embodiment of the present invention;

FIG. 2 is an elevational view of one end of the evaporator unit and housing with a portion of the end wall of the housing removed;

FIG. 3 is a view of a portion of the front wall of the evaporator unit of FIG. 2; and

FIG. 4 is a perspective view of a portion of the evaporator coil showing in more detail how the sensing bulb is clamped to the evaporator coil.

With reference to the drawings, there is shown in FIG. l a household refrigerator of the two temperature type comprising an outer shell 1 and inner shells or liners 2 and 3 spaced from the outer shell and from one another, the spaces being filled with suitable heat insulation 4. The upper liner 2 defines a fresh food storage compartment which is maintained at fresh food storage temperatures by means of an evaporator 6 while the lower liner 3 defines a freezer compartment which is maintained at sub-freezing temperatures by an evaporator unit 8. The refrigerator also includes a machinery compartment 9 containing a compressor 10 and a condenser 11. The freezer evaporator unit 8 employed for maintaining the freezer compartment at sub-freezing temperatures is preferably supported along the rear wall of the freezer com- ICC partment and forms an integral part ofthe refrigeration system or unit including 'the compressor 10, the condenser 11 and the evaporator 6. With reference alsoI to FIGS. 2 and 3 of the drawing, the evaporator unit comprises a housing including a front wall 12, end walls 13 and a rear wall 15. The evaporator coil generally indicated by the numeral 18 is contained within the housing and comprises'a refrigerant tube 20 and a defrost tube 21 extending parallel to the refrigerating tube in longitudinal contact therewith.

As is more fully described in the above-identied copending application Serial No. 832,221, one end of the evaporator coil 18 extends through an opening 23 in the rear 'wall 15 of the housing the adjacent portion of the coil extending across the housing to form a horizontal pass 22.

In accordance with the present invention a sensing bulb 24 forming part of the control circuit for controlling the operation of the refrigerating system is secured to this horizontal pass 22 by means of a one piece, sheet metal clamp 25. It will be understood that the control or sensing bulb 24 forms part of a switch mechanism which as described in the vcopending application Serial No. 832,221 terminates the defrost operation of the system when the horizontal pass 22 reaches a temperature which is sufficiently above freezing to assure complete defrosting of the evaporator coil and housing.

As the evaporator unit 8 is integrally connected to the remaining portions of the refrigerating system including the evaporator 6, the compressor 10 and a condenser 11, this system is assembled as a unit in the refrigerator cabinet, after which the electrical control circuit including the temperature sensing bulb 24 is mounted in the cabinet. The present invention is particularly concerned with an improved mounting arrangement for mounting the sensing bulb 24 on the horizontal pass 22 and which permits the insertion of the sensing bulb 24 into the housing 8 through an aperture 27 provided in the front wall 1'2 of the housing, this insertion being made after the evaporator structure 8 is mounted within the freezer compartment.

With particular reference to FIGS. 3 and 4 of the drawing, it will be seen that the sensing bulb 24 is in the form of a closed cylinder having a cylindrical side wall 29 and is connected to the switch mechanism (not shown) by means of a tube or line 30 which extends into one of the end walls 31 of the sensing bulb above the bulb axis. The reason for the tube 30 being connected above the center or axis of the sensing bulb -24 is that the tube 30 is intended to contain only the vapor component of the liquid-vapor charge contained within the sensing bulb, the liquid phase being retained at all times in the lower portion of the bulb 24.

The arrangement for clamping the bulb 24 to the horizontal pass 22 is designed to assure that the bulb 24 will always be oriented so that the line 30 is above its longitudinal axis, that is adjacent the top thereof, when the bulb 24 is positioned in a horizontal position on the pass 22 and to that end the bulb 24 is provided with a radially extending projection 33 which is adapted to be engaged by a slot '34 provided in the upper portion of the clamp 25. The clamp 25 is of generally S-shaped cross section and includes an upper loop 36 designed to substantially enclose the bulb 24, this loop including the slot 34 for receiving the orienting projection 33. When the bulb 24 is inserted in the loop 36, the bottom surface of the bulb rests on the horizontal section 38 of the clamp 25, which section forms the bottom portion of the loop 36 and the top portion of a second or lower loop or reverse bend 39 which is shaped to enclose and grip the tubes 20 and 21 forming the horizontal pass 22. The loop 39 is open along one side thereof to permit the clamp firmly anchor the clamp 25 in good heat exchange contact with pass 22.

By-,this ,-arrangement-theiclamp 25 is -irnounted on ,the 22 during assembly of ithe yevaporator structure. Thereafter, .the bulb ,'24 is `inserted :through .the :aperture .2,7 .and into loep 39 Vafter/the evaporator unit 8 includ- ;ngtclamp Z5 has -beenmounted inthe 7refrigerator Acabi- .net. lfheared `end 40 of :the loop 3,9 ,is -provided to iaeilitate insertion -,of the :bulb iinto ,the `loop 139 while Slot 34 for -,receiving,projectioniri orients 'thebulb when 1in .the assembled position.

While there has been shownanddescribed` a `particular .embodiment of the ,present invention,it .is to be understood that the invention is not `limited thereto and it is intended by the Iappended -claims -to cover Aall .modica- -(tions `,within -the -true spirit and'scopeof the invention.

What -I claim 'as `nevvand desire to secure by ALetters Patent of the United States is:

1. rlntcombination, 4an evaporator comprising a horilzontalsection `consisting `,of .a pair -of longitudinally conitacting tubes, a .temperature sensing bulb `comprising a closed 'cylinder :having a radially extending projection :on ,-onesde ythereof and a iiuid connection at one end thereof oiset from v,theaxis'of said cylinder in the direcition .of As aid projection, and a `clamp for securing .said .bulb to ysaidhorizontal fsection, said clamp consisting of a ione-,piece sheet -rnetal body of generally S-shape vto :provide :a;loop `for receiving said bulb zand areverse `bend for engaging kboth ;of said tubes, `said .clamp having a 4 slot in the upper portion of said open loop for receiving said projection and maintaining said yiluid ,connection above the axis of said cylinder.

2. In combination, an evaporator unit including a housing containing an evaporator comprising a horizontal section consisting of apair of Alongitudinally contacting tubes, `a temperature vsensing bulb comprising a closed cylinder anda radially extending projection on one-side thereof and arfluidrconneetion at'one end thereof offset from the axis of -said cylinder in .the Ivdirection of said projection and extending through said housing, and a ,clamp vfor `securingvsaid bulb to said horizontal section, -said clamp consisting of a one-piece sheet metal body of generally S-shape to provide an open lloop for receiving said bulb anda Areverse `bend for engaging both of said tubes, said-clamp having aslot in the upper portion of vsaid-open loop for receiving said `projection and mainztaining saidruidconnection above .the axis of said cylinder.

References -Citerl in the ,le of lthis patent UNITED -S-ATES PATENTS 

